The policy of vietnamization of the armed conflict in South Vietnam was implemented by President Richard M. Nixon and was the result of the 1968 Tet Offensive, which was given a somewhat distorted journalistic coverage at the time, causing even more public demonstration against the war. The policy of vietnamization consisted of expanding, equipping, and training South Vietnam’s forces, assigning them an ever-increasing combat role as the US combat troops were reduced in stages. This withdrawal of US fighting forces applied only to ground combat troops, not to US Air Force units which would continue with their operations to support South Vietnam’s Army.
The policy of vietnamization began in February 1969 and extended until 1973. Although it was a deliberate policy enforced by the Nixon Administration, the name was rather accidental. At a January 28, 1969, meeting of the National Security Council, GEN Andrew Goodpaster, deputy to GEN Creighton Abrams, commander of the Military Assistance Command, Vietnam, said the Army of the Republic of Viet Nam (South Vietnam’s Army) had been steadily improving, and the point at which the war could be "de-Americanized" was close. Melvin Laird, the Secretary of Defense, agreed with the point, but not with the language: "what we need is a term like ‘Vietnamizing’ to put the emphasis on the right issues." Nixon immediately liked Laird’s word.
Vietnamization fit into the broader Nixon Administration detente policy, in which the United States no longer regarded its fundamental stategy as containment of Communism, but a cooperative world order in which Nixon and his chief adviser Henry Kissinger were basically "realists" in world affairs, interested in the broader constellation of forces, and the biggest powers. Nixon had ordered Kissinger to negotiate basic U.S.-Soviet policy between the heads of state via Kissinger and Dobrynin, with the agreements then transferred to diplomats for implementation. In like manner, Nixon opened high-level contact with China. U.S. relations with the Soviet Union and China were seen as far more important than the fate of South Vietnam, which certainly did not preclude South Vietnam maintaining its own independence.
The vietnamization of the war had two components. The first was strengthening the armed force of the South Vietnamese in numbers, equipment, leadership and combat skills. The second component was the extension of the pacification program in South Vietnam. The first was achievable, but it would take time. For the United States, it was trivial to have a US helicopter pilot fly in support, but helicopter operations were too much part of ground operations to involve US personnel. As observed by LTG Dave Palmer, to qualify a South Vietnamese Army candidate for US helicopter school, he first needed months of English language training to be able to follow the months-long training, and then additional field time to become proficient. In other words, adding new capabilities to the South Vietnamese Army would often take two or more years.